Oil cooler controlling structure



y 1944. H. CHISHOLM, JR 2,353,546

OIL COOLER CONTROLLING STRUCTURE Filed Sept. 26, 1942 4 Sheets-Sheet lJuly 11, 1944. H. L. CHISHOLM. JR 2,353,546

OIL COOLER CONTROLLING STRUCTURE Filed Sept. 26, 1942 4 Sheets-Sheet 2.zc/jfl July 11, 1944.

H. L. CHISHOLM. JR

OIL COOLER CONTROLLING STRUCTURE Filed Sept. 26, 1942 4 Sheets-Sheet 3July 11, 1944. H. L. CHISHOLM, JR

OIL COOLER CONTROLLING STRUCTURE Filed Sept. 26, 1942 4 Sheets-Sheet 4MED U wry/l; 6%; (skull/mi Patented July 11, 1944 OIL COOLER CONTROLLINGSTRUCTURE Harry L. Chisholm, Jr., Buffalo, N. YQassignor toHoudaille-Hershcy Corporation, Detroit, Mich., a corporation of MichiganApplication September 26, 1942, Serial No. 459,809 r 6 Claims. (01.236-35) My invention relates to controlling structure for oil coolerssuchas are used in connection with hydrocarbon engines, such as aircraftengines, for keeping the lubricating oil in the most desirable conditionfor eflicient lubrication under the varying temperature conditionsencountered. The invention relates particularly to improved valvingassembly for controlling the oil flow through the cooler forming jacketand radiator, and for controlling the flow of oil to and from a cylinderstructure which operates shutters provided on the cooler.

My invention may be considered as embodying improvements over the oilcooler controlling structure disclosed in my pending application SerialNo. 453,299, filed August 1, 1942.

In my present application, the structure for controlling the flow of theoil through the cooler is substantially the same as that in my pendingapplication, and under normal conditions, like in my pendingapplication, the operation of the shutter controlling cylinder structureis controlled by the pressure of the flow through the cooler.

An important object of my present invention is to provide furthercontrol of the fluid flow for the shutter operating cylinder structurein the form of thermostat controlled means responsive to the temperatureof the flow through the cooler in such manner as to prevent closing oropening of. the shutters during increase or decrease of the rate of flowthrough the cooler.

Another important object is to provide acontrol for fluid flow to theshutter controlling cylinder structure involving a relief valve and athermostatically operated valve in parallel therewith, with the reliefvalve, upon closure of the thermostatically controlled valve, beingresponsive only to a predetermined pressure built up in the coolertoopen up for flow of fluid to the cylinder structure, and with thethermostatically controlled valve operating in response to temperatureto open for freer flow to the cylinder structure for opening or closingmovement of the shutters.

The above referred to and other features of my invention are embodied inthe structureshown on the drawings, in which drawings- Figure l is aside elevation, partly in section, of an oil cooler with my improvedvalvingassembly mounted thereon; t

Figure 2 is an enlarged section on plane II-II of Figs. 1 and a sectionon plane II-II of Fig. 3, but with the piston at the inner end of thecylinder.

Figure 3 is a section on plane IIIIII of Fig. 2

but with the piston at the outer endof the cylinder;

Figure 4 is a section on plane IV-'IV of Fig. 3;- Figure 5 is a sectionon plane-V'-V of Fig. 3; Figure 6 is a section on plane VI-VI of'Fig. 3;Figures '7 to 13 inclusive are sections-on plane VIVI of Figs; 2 and 3'of the controlling valving assembly for the cylinder structureshowingthe assembly in various positions during operation of thestructure. j Referring to Fig. l, R indicates the radiato structure andV the valve structure. The radiator structure shown is of a conventionaltype, comprising the cylindrical shell l0 through which extend the tubesI l soldered or otherwise secured together at their ends and exposed forflow there-"- through of air during running of the vehicle or airplane.Surrounding the shell l0 is-the warms ing jacket I2 which is connectedat its lower side with the radiator through a passage I3. Mounted on topof the warming jacket is the base plate I4 on which the valve structureVseats and-i secured as by screws l5. Referring to Figs. 2 to 6, thevalve'structure V comprises the housing lB-having the inlet I1 for theoil from the engine E, and theoutlet l8 for return flow from theradiator and warming jacket to the sump 0 from which the oil to theengineis delivered by a pump P (Fig. 1'). Within the housing atoppositesides of the inlet I1 are'the transverse walls'20 and 2| betweenthe sides and top of the housing. The lower ends of the trans versewalls are connected bythe horizontal wall 22 extending between the sidesof the housing; The walls 20, 2| and 22, together with the sides and topof the housing l6 define a valve chamber 24. Partly surrounding thewalls which define the valve chamber '24 is the inlet space;-28,-theoutlet passageway 29 from which'registers with the passageway 30 throughthe base l4"on;the warming jacket, the jacket having the inlet 3icommunicating with the passageway-30. The wall 20 has the passageway 32therethr ough for connection of the valve chamber- 24 with the space 33with which the outlet -I8 communicates; The passageway 32' in the wall2| serves toconnect the valve chamber with the space 28. -Within thevalve chamber is a valvingassembly comprising the annular valve 34 forclosing the passageway 32, and the annular valve 35 for closing thepassageway 32'. 'Betweenthese .valvesis a thermostat T which may be ofthe type known'in the trade as the Vernet type. The thermostat comprisesthe body or container 36 from which the neck 31 extends whiehreceivesthe plunger 38 to be acted upon by the thermostatic material within thecontainer which, upon expansion due to rising temperature, will exertpressure against the plunger 38 to shift the container toward the left(Fig. 2) the plunger at its outer end abutting an adjustable abutment 39mounted in the adjacent end wall of the housing I 6.

The neck 31 extends axially through the valve 35 and has rigidly securedthereto a collar 45 which has a spherical surface against which thevalve 35 is normally held by a spring 4!. Formed on the inner end of thethermostat body is a stud 42 to which is rigidly secured a sleeve 43which at its inner end has a shoulder 4 Slidably mounted'on the sleeveis the annular relief or blowoif valve 45 which seats on the outer sideof the valve 34. The valve 34 has fingers 46 for engaging the shoulder44 on the sleeve 43 to be normally held in this position by the spring4! i between the valves 34 and 35. gages against the outer side of theblowoff'valve 45, a cage 48 extending from the wall 25 forming theabutment for the outer end of the spring. The spring-41 is weaker thanthe spring 4! and the valves 34 and 35 are therefore normally held inseating engagement to closethe passageway through the valve 34. Thisunitary assembly comprising the thermostat T, the valves 34, 35 and 45and the spring 4| is shiftable axially by the thermostat, the axialmovement being guided by guide wings 49 on the valves 34 and 35. Thethermostat T is adjusted so that at temperature belw, say'100 F, thethermostat will be in its contracted position shown on Fig. 3, the valve34 being open and the valve 35 closed, the spring 41 effecting suchshift of the assembly. As the thermostat'is subjected to highertemperatures, the material therein will expand, and as the spring 4| isstronger than the spring 41', the thermostat body with the valvesthereon will be shifted away from the plunger 38 toward the left foropening of the valve 35 and closing of the valve 34 to the positionshown on Fig. 2. The thermostat may continue to expand after the valve34 has been seated and, unless means were provided to allow suchovertravel, the thermostat body might burst. To permit overtravelwithout fracture, the sleeve 43 attached to the thermostat body slidesto the left within the blowoff valve 45, the shoulder 44 on the sleeveleaving the fingers 45 on the valve 34, the valve 34 being then seatedby the spring 4! to close the passageway 32 and the valve 35 being movedby the spring 4| to the left beyond its normal fully open position untilthe overtravel of the thermostat ceases. 7

Referring to Figs.' 3 and 5, a horizontal wall 50 extends inwardly'fromthe left end wall of the housing 16 and transversely between the sidewalls of the housing. A cylindrical wall portion extends between thewall 53 and the top wall 52 of the housing to provide a seat for acylinder 53, the axis of this cylinder'being parallel with but to oneside of the axis of the valve assembly in valve chamber 24. At its outerend the cylinder has the flange 54 engaging against the adjacent leftend of the housing IS, the outer end of the cylinder bein closed by ahead 55 between which. and the end of the housing It; the cylinderflange 54 extends to be clamped as by screws 555 threading into flanges5'! on the housing (Fig. 4).

Referring to Figs. 3 and 6, an annular valve seat 58 issecured inthebottom wall of the hou ing I 6 between the inner end of the cylinder 53and the wall of the valve chamber 24. The

A spring 4'1 en passageway 58 through the valve seat 5-3 communicateswith the passage 55 through the base hi on the warming jacket iii, thewarming jacket outlet 5! registering with the passageway 53. Between thewarming chamber inlet 35 and the outlet 5! a partition wall 52 extendstransversely across the warming jacket 50 that oil flow into the inlets!must travel circumferentially around the warming jacket before reachingthe outlet 6|.

. To the left of the valve seat 53, Figs. 3 and 5, a valve seat issecured in the bottom wall of the housing It with its passageway 54 inalignment with the radiator outlet nipple 65 which extends into thepassageway 55 in the base M.

A valve 51 is engaged by a spring 58 tending to hold it seated againstthe inner side of the seat-'58, a cage 53 anchored to the seat 58forming the abutment for the outer end of the spring. A similar valve itis engaged by a spring Tl tending to hold it seated against the innerside of the seat 53, a cage 72 anchored to the seat forming the outerabutment for the spring, the spring H being lighter than the'spring E8.

The operation of'the structure thus far described is as follows. Beforethe engine is started, the' temperature is usually such that thethermostat T is contracted. as shown on Fig. 3, the valves 34 and 35being respectively open and closed. The thermostat is adjusted to remaincontracted under say F., and as the engine now starts, the pump D driventhereby will draw oil from the sump O and force it through the enginebearings, the oil flowing from the engin into the inlet l1 around thevalve assembly and past the open valve 34 through the passageway 32 intothe space 33 and from there directly back through the outlet I 8 to thesump (Fig. 1). This permits rapid warming of the oil in the sump sinceit receives no cooling flow from the radiator. The warmed oil, engagingwith the thermostat element '1', raises the temperature thereof above100 F. to actuate the thermostat to open the valve 35 and to close thevalve 34 so that oil may then flow into the inlet space 28 for flow intothe warming jacket through the inlet 3!. Usually the oil is sluggish inthe cooler before the engine is started, and a pressure is built up inthe valve chamber which, together with the warm oil, will soon forceflow of the oil through the jacket. The built up pressure will beagainst the valve 68 which is set to remain closed until a pressure, sayof .30 lbs..per sq. in., is reached, and when the valve opens, the flowthrough the warming jacket will begin, the discharged oil flowingthrough the outlet it back to the sump. During this time some oil may beforced from the jacket through the inlet passageway l3 and through theradiator and, past the valve 10 whose spring I! is comparatively light.This light flow through the radiator assists in the warming thereof andas the radiator warms and the resistance to flow through it decreases,the rate of fiow increases until a temperature, say F. is reached, thepressure through the jacket then dropping down below 30 lbs. per sq. in.so that the spring 68 closes the valve 61, all of the oil then flowingthrough the radiator. Should the oil in the radiator suddenly becomesluggish or congeal. pressure will again build up in the jacket untilthe radiator has again become warmed up for normal flow therethrough.Should the oil in both the radiator and the warming jacket suddenlycongeal while the valve 34 is closed by the thermOStat. the built uppressure in the valve chamber 24 will open the blowofl valve 45 for flowor the engine oil through the passageway 32 and outlet space 33 and backto th sump until the pressure built up by the oil from the engine canreestablish flow through the jacket.

Describing now the shutter controlling mechanism, a piston 13 within thecylinder 53 has the rod 14 extending therefrom through the cylinder head55, the rod being connected through linkage 15 anchored at 15, with thebar Hiconnected with the shutters 11 on the radiator R. The piston rodhas the bore 18 into which extends the head 19 of the cylindrical valvebar 80. The valve bar extends through the inner wall 8| of the cylinderto which it is connected by threading 82 to be substantially heldagainst axial movement relative to the cylinder but to be rotatable. Thevalve bar head 19 has diametrically opposit longitudinally extendinghelical grooves 83 and 84 in which engage the ends of fingers 85 and 86projecting radially inwardly from a ring 81 secured to the inner side ofthe piston 13, as by rivets 81'. Due to the connection of the piston rodwith the shutter operating linkage 15, the piston is held againstrotational movement in the cylinder 53 but, as the piston moves inwardlyand outwardly in the cylinder, the cam fingers 85 and B5 engaging in thehelical grooves will cause corresponding rotational movement of thevalve bar. The pitch of the grooves is comparatively small so that for acomplete inward or outward movement of the piston the valve bar will brotated through a comparatively small angle, say about The inner end ofthe valve bar 89 projects through the wall 29 into the valve chamber 24(Figs. 2 and 4) and the-valve bar has the bore 88 therethrough for flowof fluid from the valve chamber. A cross wall in the bore has apassageway 89 therethrough and on its outer side provides a seat for aball valve 90. Threading into the outer end of the bore 88 is anabutment plug 9| between whos inner end and the valve 90 is interposedthe spring 92 which tends to hold the valve 90 seated to close thepassageway 89.

A spring assembly 93 in the cylinder 53 tends to shift the piston 13 toits inner position shown on Fig. 2, ports 94 in the, valve bar servingto connect the valve bore with the inner end of the cylinder 53 behindthe piston so that, upon flow of oil under pressure through the valvebar bore and into th cylinder, the piston will be shifted outwardly foractuation of the linkage assembly 75 to cause closing movement of theradiator shutters.

Just inside the passageway 89 controlled by the valve 90, one or moreports are provided in the valve bar, two such ports 95 and 95' beingshown diametrically opposite. Adjacent to the outer side of thepassageway 89 the bar has the diametrically opposite ports 99 and 96.Receiving the valve bar is a valve collar 91 rotatable on the bar butheld against axial movement by being located between the inner wall ofthe cylinder 53 and a snap ring 98 surrounding the valve bar. The rotarymovement of the valve collar is controlled by a thermostat 99, shown inthe form of a spiral, having one end anchored to .the valve collar andthe other end anchored to a lug I00 on the inner wall of the cylinder53.

The valve collar has the two diametrically op-- posite longitudinallyextending ports llll and NH" adapted, during certain settings of thevalve collar, to connect respectively the valve bar ports 95 and 96 and95' and96'; and the valve collar during-other settings. shuts off flowthrough these ports." When the valve bar ports are closed by the valvecollar, there can be no fluid flow through the valve bar bore to thecylinder until the pressure in the valve chamber 24 is suflicient tocause unseating oftheyvalve 9|] against the resistance of the spring 92.However, when the valve collar is set for registration of its ports withthevalve bar lpOItS; fluid may flow from the chamber through the valvebar bore around the valve and into the cylinder.

By means of the threaded abutment 9| in the outer end of the piston rod,the desired tension of the spring 92-may be adjusted for, and thisalbutment' has the bore I82 therethrough so that oil under pressure mayflow from the valve chamber 24 through the valve bar '48 and throughports 94 into the cylinder-behind the piston, and also through the boreI92 of the'abutment member and against the outer wall of the-piston rod,so that maximum piston surface is. available for the fluid to efiectoutward movement of the piston against the resistance of thesprings 93,for 010- sure movement of the shutters. Upon outward movement of thepiston, the oil in the outer part of the cylinder may escape through thepassageway l03 into the outlet space 33 which is connected through theoutlet l8 with the sump 0. Upon cessation of fluid flow from the valvechamber 24 through the valve bar into the cylinder, or upon decrease inpressure in the valve chamber 24, and corresponding inward movement ofthe piston by the spring assembly 93, the oil may escape from the innerend of the cylinder by Way of a relief passage I04 through the innerwall of the cylinder (Fig. 3), and some of this oil may also escapealong the threading 82 into the outlet space 33. So long as the pressureof the flow from the valve chamber 24 into the cylinder lbalances thepressure of the springs 93 and the outflow of oil from the inner end ofthe cylinder, inward movement of the piston will be stopped and theshutters held in a correspond- 1 ing open position.

Describing now the operation of the shutter controlling mechanism,before the engine is startedand the oil in the cooler is sluggish ormore or less congealed, the warm oil from the engine flows into thevalve chamber 24 and out past the open valve 34 into the outlet space 33and through the outlet [8 directly back to the sump, the thermostat Tsoon becoming heated to shift its valve'assembly for closure of thevalve 34 and opening of the valve 35, the valve ports 95, and 96, 95being then closed by the valve collar 91, as shown clearly on Fig. 7.The spring 68 controlling the outlet valve 61 from the warming jacket isdimensioned so that it will not open until a pressure of say 30lbs. persq. in. is reached. The flow through the jacket being sluggish, theincoming engine oil will build up a pressure in the valve chamber 24 andas soon as this pressure reaches 30 lbs. per sq. in., the valve 90 inthe valve bar will be unseated against its spring 92 which is set toresist opening of the valve until a pressure of 30 lbs. per sq. in. isreached. Upon opening of the valve 90 fluid will flow from the valvechamber 24 through the passageways 89 and ports 94 into the cylinder forquick outwardmovement of the piston to close the shutters and then theoil in the warming jacket and in the radiator is quickly warmed up forfreer flow and under pressure less than 30 lbs. per sq. in. so that thevalve 61 will be closed'by its spring 68 and all of thefluid willeventually be through the radiator past the valve 10 which is resistedby the comparatively light spring H. The thermostat controlling thevalve collar 91 is in the path of the oil flow from the cooler throughthe outthe [piston was in. Immediately after reduction of the pressurein valve chamber 24 below 30 lbs. per sq. in., the valve 9!! is closedby its spring 92 but the thermostat 99, in response to the-temperatureof the oil flowing from the warming jacket, turns the valve collar inclockwise direction to bring its ports I! and I0! into registration withthe valve lbar ports, as shown on Fig. 9, so that, after closure of thevalve 90, the fluid flow fromthe valve chamber 24 is through the valvelbar ports and the valve 'collar ports into the cylinder behind thepiston and the piston will be held out to keep the shutters closed,pressure much less than 30 lbs. per sq. in., say as low as 8 lbs. persq. in, in the valve chamber 24, being suflicient to hold the piston outThe rotation of the valve collar to bring its ports into registrationwith the valve bar ports takes place while the temperature rises to saynear 140F. Figs. 3 and 6 shows the arrangement of the partscorresponding with Fig. 9, except that the valve assembly controlled bythe thermostat T will be in position to close the valve 34 and open thevalve 35.

As the temperature now increases the valve collar will continue torotate and will move its ports away from the valve bar ports, as shownon Fig. 10, and as soon as the ports move out of registration, furtherflow from the valve chamber 24 into cylinder will stop, as at thistimethe pressure is below 30 lbs. per sq. in. and the valve 90 isclosed. With the flow of fluid into the cylinders behind the pistonstopped, the springs 9-3 become efiective to move the piston inwardlyfor movement of the shutters toward open position so that cooling airmay flow through the radiator. As the piston is moved inwardly by thesprings, the fluid at the inner end of the cylinder flows graduallythrough the more or less restricted relief outlet m4, and some of theoil will escape past the threading 82 and some oil may also leak pastthe piston. Upon such inward movement of the piston, the engagement ofthe piston fingers B and 86 in the valve bar helical grooves will causerotation of the valve bar in clockwise direction to follow the turningmovement of the valve collar. If the temperature keeps rising, the valvecollar will continue to move its ports away from the valve bar ports sothat the piston may move entirely inwardly for complete opening of theshutters. Figs. 2 and 11 shows the arrangement of theports when thetemperature reaches say 180, and this temperature may be the temperaturedesired for normal running conditions and, when this temperatureisreached, the valve collar 9! will have been rotated 180 from theposition shown in Fig. 7. Should the temperature decrease, thethermostat 99 will rotate the valve collar back in counterclockwisedirection, as shown on Fig. 13, to bring its ports back intoregistration with the valve bar ports, so that oil may flow from thevalve chamber 24 into the temperature again reaches 189.

cylinder to shift the piston out for closing movement of the shutters toreduce the air flow through the radiator. During such outward movementof the piston the valve bar will be rotated in counterclockwisedirection. Referring to Fig. 13, if the temperature at the thermostat 39decreased to, say and remained there, and the collar were shifted due tothis temperature change to just bring its ports into registration withthe Valve bar ports, then the fluid flow from the valve chamber 24intothe cylinder will move the piston out and the accompanying rotation incounterclockwise direction of the valve bar will move the valve barports out of registration with the valve collar ports and further flowfrom the valve chamber 24 will stop, and if the temperature decreasesfurther, the valve collar ports will again come into registration withthe valve bar ports for further outward movement of the piston andcorresponding further movement of the shutters. However, as soon as thetemperature increases and the valve collar is rotated in clockwisedirection, its'ports will cooperate with the valve bar ports for fullopening of the shutters when the Thus the pressure of the cooler oilflow and the temperature thereof will cooperate to control the pistonoperation for setting of the shutters for proper operation of theradiator.

If, while the temperature in the control as sembly is at normal, say theairplane suddenly climbs into subzero temperature and the oil in thecooler is therefore suddenly congealed, the pressure in the valvechamber 24 will rapidly rise to 30 lbs. per sq. in or over, and, as at180 temperature Within the control assembly the valve collar shuts ofi?the valve bar ports, this built up pressure will force open the valve 96for flow of oil from the valve chamber 24 into the cylinder to quicklymove the piston out for closure of the radiator shutters (see Fig. 12).Owing to the sudden congealing of the oil in the cooler, the built uppressure may rise beyond 30 lbs. per sq. in. in which event the blowofivalve 45 in the valve chamber 24 will open up against the resistance ofthe spring 41, which resistance may be say '75 lbs. per square inch. Theoil from the engine will then flow directly back to the sump until thepressure has been sufliciently reduced for reclosing of the blowoi'fvalve. After closure of the shutters by the piston, the pressure andtemperature of the oil from the engine will soon thaw out the cooler forflow therethrough and reduction of the pressure below 30 lbs. per sq.in. so that the valve 90 will close and the spring 93 will return thepiston and shutters to the position decreed by the angular setting ofthe valve collar by the thermostat 99.

It may be desirable to adjust the setting of the thermostat 99 and thevalve collar relative to the valve bar. As shown this is accomplished byrotating the cylinder 53 to which one end of the thermostat is anchored.As shown in Fig. 2, the cylinder flange has the extension Hi5 projectingoutwardly so that, after loosening of the screws 56, the cylinder may berotatably set for the desired setting of the thermostat, and after suchsetting the screws 56 are retightened.

If, during normal operation of the cooler at say 180, the rate of oilflow from the engine through the cooler is increased with correspondingincrease of pressure in the valve chamber 24, this pressure cannoteffect closing movement of the shutters because the valve 9? and thesetting of the valve collar by the thermostat, shuts ofi flow from thevalve chamber to the cylinder.

.this increase in pressure due to increasing rate of flow. reaches 30lbs. per sq. in, which is very unlikely, the valve 90 will remainclosed.

Although a pressure of 30 lbs. per sq. in. in the;

Unless valve chamber 24 may be required to open the valve 90 for oilflow into the cylinder, a much less pressure, say for example 8 lbs. persq. in., in

. thevalve chamber'will be sufficient to hold the .piston in its outerposition for closure of the shutters.

l during a warming up period for bringing the cooler oil to its normaltemperature of 180, and dur- Such closure of the shutters is usually ingsuch warming up period, as indicated on Fig.

' 9, the thermostat will set the valve collar for ex posure of the valvebar ports for oil flow to hold the piston out with the shutters closed.If now,

duringsthis warming up period, the rate of flow fromthe engine shoulddecrease with correspond- I ment of the piston for opening of theshutters will be controlled in a manner hereinbefore explained.

I have shown a practical and efficient embodis ment of the features ofmy invention but I do not desire to be limited to the exactconstruction, arrangement and operation shown and described, as changesand modifications may be made without departing from the scope of theinvention.

I claim as follows:

1. A controlling structure for an internal combustion engine oil coolerhaving shutters thereon, comprising a housing having an inlet chamberfor receiving the oil from the engine for delivery to the cooler, acylinder having a piston connected with the cooler shutters foroperation thereof, spring means tending to move said piston inwardly foropening movement of the shutters, a valve member in the form of a barbetween said inlet chamber and said cylinder and having a boretherethrough for the flow of oil from the chamber to the cylinder, aspring pressed check valve in said bore closing said bore against flowtherethrough under normal fluid pressure in said inlet chamber but beingresponsive to predetermined increased pressure to open said bore forflow of fluid to the cylinder to efiect outward movement of the pistonfor closing movement of the shutters, ports at opposite sides of saidcheck valve extending from said valve bar bore to the exterior thereof,a valve collar movable on said valve bar and having ports to be broughtinto registration with said valve bar ports to afford flow passagewayfrom the inlet chamber to the cylinder when said check valve is closed,and a thermostat subjected to the temperature of the discharge oil fromthe cooler for setting said valve collar in accordance with variationsin temperature to open or close said valve bar ports whereby themovement of said piston and shutters will be in accord with the pressurein said inlet chamber and the temperature of the discharge cooler oil.

2. A controlling structure for an internal combustion engine oil coolerhaving shutters thereon, comprising a housing having an inlet chamberfor receiving the oil from the engine for delivery to the cooler, acylinder having a piston connected with the shutters for controlthereof, spring opening of the shutters, avalve member inthe form of abar between said inlet chamber andsaid cylinder having a boretherethroughfor flow of oil from the inlet chamber into the cylinderbehind the piston, a spring pressed check valve in said bore closingsaid bore against flow into the cylinder under normal fluid pressureconditions but opening said bore under predetermined increased pressureconditions'for fiow of oil into the ,cylinder for outward movement ofthe piston, ports on opposite sides of said check valve extend ing fromsaid valve bar bore to the outer side thereof,;a-valve collar rotatableon said valve bar and having ports for registering with said 5 valve barports for flow of oil from the inlet chamber into the cylinder when saidcheck valve is closed, a camming connection between said piston and saidvalve bar effective during axial movement of the piston to rotate saidvalve bar for setting of its ports relativeto said valvecollar ports,

, a thermostat for rotating said valve collar in accordance withvariation in temperature of the oil discharged from the cooler forsetting of said collar ports relative to said valve bar ports, wherebythe rotational movements of said valve bar and valve collar will controlthe connection or disconnection of the valve bar ports and the valvecollar ports and. the movement ofsaid piston and the shutters will be inaccord with; the pressure in said ,inlet chamber and the temperature ofthe discharged cooler oil while said check valve is closed. '3. Acontrolling structure for an internal commeans tending to move saidpiston inwardly for 78 bustion engine oil cooler having shuttersthereon, comprising a housing having an inlet chamber for receiving theoil from the engine for delivery to the cooler, a cylinder having apiston connected with the shutters, a duct for flow of oil from theinlet chamber into the cylinder, a spring pressed check valve in saidduct shutting ofi flow therethrough under normal pressure conditions insaid inlet chamber, a by-passageway around said check valve for flow ofoil to said cylinder when said check valve is closed, a control valvefor said bypassageway rotatable on said duct, and thermostat means forsetting said control valve in accordance with the temperature of thedischarged cooler oil, said thermostat means under comparatively lowtemperature setting said control valve for closure of saidby-passageway, said check valve during closure of said by-passagewaybeing responsive to abnormal pressure increase in said inlet chamber toopen passageway through said duct for flow of oil for moving said pistonfor closure movement of the shutters.

4. A controlling structure for an internal combustion engine oil coolerhaving shutters thereon, comprising a housing having an inlet chamberfor receiving the oil from the engine for delivery to the cooler, acylinder having a piston connected with the shutters, a duct betweensaid inlet chamber and said cylinder for fluid flow to said cylinder andoperation of said piston to control the shutters, a check valve in saidduct and a spring for holding it closed against flow therethrough undernormal pressure in said chamber, a bypassageway around said check valvefor flow of oil to said cylinder when said check valve is closed, acontrol valve for said by-passageway surrounding said duct, andthermostat means for setting said control valve in accordance with thetemperature of the cooler oil discharge flow to open or close saidby-passageway, said check valve during closure of said by-passageway bysaid control valve responding to predetermined pressure increase in saidchamber to open said duct for flow to the cylinder' for movement of the;piston-'to elosetheshutters.

- A controlling structure for an internal combustion engine oil-coolerhaving shutters thereon, comprising-an inlet chamber for receiving'theoil 'fro-m' the engine for delivery to the cooler, a

cylinder-havinga piston therein connected with the cooler shutters forcontrol thereof, spring means tending to shift said piston for openingof --the -shutters, a duct between said inlet chamber andsaidcylinder, acheck valve in said duct respam-ye only to predetermined abnormal pres-'-sure iri said chamberto open said duct for flow, portsdnsaid-duct atopposite sides of said check valve, a control valve movable on said ductand having ports; thermostat means responsive to the temperature of thecooler discharge flow for setting said control valve to'shut ofi saidduct ports orto register its ports withthe duct ports to define alay-passageway around said check valve for flow into the cylinder'w-hensaid check valve is-closed for outward movement of the piston to movethe-shutters to closing position under pressure less than that necessaryto open said check valve.-

-- 6. A controlling structure for an internal cominwardly for openingmovement of the shutters, a valve member in the form of a bar betweensaid inlet chamber and said cylinder and having a bore therethrough forflow of oil from the chamber to the cylinder, a spring pressed checkvalve in said bore closing said bore against flow therethrough undernormal fluid pressure in said inlet chamber but being responsive to.predetermined increased pressure to open said bore for flow of fluid tothe cylinder to effect outward movement of the piston for closingmovement of the shutters, ports on opposite sides of said check valveextending from said valve bar bore to the outer side thereof, a valvecollar rotatable on said valve bar and having ports for registering,with said valve bar ports for flow of oil from the inlet chamber intosaid cylinder when said check valve is closed, a thermostat subjected tothe temperature of the discharged oil from the cooler for setting saidvalve collar in accordance with variations in temperature to open orclose said valve bar ports, and a connection between said piston andvalve bar efiective upon axial movement of said piston to rotate saidvalve bar to move its ports into or out of registration with said collarports for continuation of flow or stoppage of flow into the cylinderwhile said check valve is closed until said thermostat operates saidcollar for setting of its ports for reclosure or reopening of said valvebar ports.

HARRY L. CHISHOLM, J R.

